Why is nginx running on port 8080 but not 81?

Question

Based on brew info nginx the terminal output is telling me that nginx is running on port 8080 by default:

The default port has been set in /usr/local/etc/nginx/nginx.conf to 8080 so that nginx can run without sudo.

This is the full output:

$ brew info nginx
nginx: stable 1.19.0 (bottled), HEAD
HTTP(S) server and reverse proxy, and IMAP/POP3 proxy server
https://nginx.org/
/usr/local/Cellar/nginx/1.19.0 (25 files, 2.1MB) *
  Poured from bottle on 2020-06-16 at 17:55:46
From: https://github.com/Homebrew/homebrew-core/blob/master/Formula/nginx.rb
==> Dependencies
Required: [email protected] ✔, pcre ✔
==> Options
--HEAD
    Install HEAD version
==> Caveats
Docroot is: /usr/local/var/www

The default port has been set in /usr/local/etc/nginx/nginx.conf to 8080 so that
nginx can run without sudo.

nginx will load all files in /usr/local/etc/nginx/servers/.

To have launchd start nginx now and restart at login:
  brew services start nginx
Or, if you don't want/need a background service you can just run:
  nginx
==> Analytics
install: 33,973 (30 days), 101,534 (90 days), 407,985 (365 days)
install-on-request: 33,387 (30 days), 99,128 (90 days), 394,576 (365 days)
build-error: 0 (30 days)

My Mac OS is Catalina 10.15

However, when I go to look at the nginx.conf in /usr/local/etc/nginx/nginx.conf I do not see that the nginx port is open on 8080. I see it open on port 81:

server {
        listen       81;
        server_name  localhost;
    ....
    ....

When I go to visit http://localhost:8080/ I get the nginx welcome message. However when I go to visit http://localhost:81/ I get a "site can't be reached" ERR_CONNECTION_REFUSED error.

How is nginx running on port 8080 without such a specification in the nginx.conf file? And why is nginx not running on port 81 which the conf appears to suggest it should.

Here's the full nginx.conf:

# cat /usr/local/etc/nginx/nginx.conf

#user  nobody;
worker_processes  1;

#error_log  logs/error.log;
#error_log  logs/error.log  notice;
#error_log  logs/error.log  info;

#pid        logs/nginx.pid;


events {
    worker_connections  1024;
}


http {
    include       mime.types;
    default_type  application/octet-stream;

    #log_format  main  '$remote_addr - $remote_user [$time_local] "$request" '
    #                  '$status $body_bytes_sent "$http_referer" '
    #                  '"$http_user_agent" "$http_x_forwarded_for"';

    #access_log  logs/access.log  main;

    sendfile        on;
    #tcp_nopush     on;

    #keepalive_timeout  0;
    keepalive_timeout  65;

    #gzip  on;

    server {
        listen       81;
        server_name  localhost;

        #charset koi8-r;

        #access_log  logs/host.access.log  main;

        #error_page  404              /404.html;

        # redirect server error pages to the static page /50x.html
        #
        error_page   500 502 503 504  /50x.html;
        location = /50x.html {
            root   html;
        }


        # proxy the PHP scripts to Apache listening on 127.0.0.1:80
        #
        #location ~ \.php$ {
        #    proxy_pass   http://127.0.0.1;
        #}

        # pass the PHP scripts to FastCGI server listening on 127.0.0.1:9000
        #
        #location ~ \.php$ {
        #    root           html;
        #    fastcgi_pass   127.0.0.1:9000;
        #    fastcgi_index  index.php;
        #    fastcgi_param  SCRIPT_FILENAME  /scripts$fastcgi_script_name;
        #    include        fastcgi_params;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #    deny  all;
        #}
    }


    # another virtual host using mix of IP-, name-, and port-based configuration
    #
    #server {
    #    listen       8000;
    #    listen       somename:8080;
    #    server_name  somename  alias  another.alias;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}


    # HTTPS server
    #
    #server {
    #    listen       443 ssl;
    #    server_name  localhost;

    #    ssl_certificate      cert.pem;
    #    ssl_certificate_key  cert.key;

    #    ssl_session_cache    shared:SSL:1m;
    #    ssl_session_timeout  5m;

    #    ssl_ciphers  HIGH:!aNULL:!MD5;
    #    ssl_prefer_server_ciphers  on;

    #    location / {
    #        root   html;
    #        index  index.html index.htm;
    #    }
    #}

    include servers/*;
}

Answer 1

Have you tried to restart/reload Nginx yet? In order for the configuration change to take effect, you need to reload it.

You can use this command on Mac OSX to reload Nginx: sudo nginx -s reload